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Op Amp Labs mixer?

Discussion in 'Pro Audio Equipment' started by claymation, Dec 8, 2007.

  1. claymation

    claymation Guest

    Hello, I'm new here. I just bought an OpAmp Labs mixer at a garage sale for $50. It's the 8 channel version of the 1204-tv. I'm not sure of the model #, but the preamps and eq sections are the same as the 1204. I saw one selling on ebay for about 100 times what I payed! Can anyone else tell me more about this piece? thanks!
     
  2. RemyRAD

    RemyRAD Well-Known Member

    claymation So cool!

    I sure can as I assembled one, a 24 input version with 8 output buses. A stereo bus and 4 effects sends back in 1978.

    I still own two thirds of that console. LOL! A lot of folks felt that they overloaded too easily. I didn't think so as I slightly changed my gain structure from what was recommended and we never had any overload problems. In fact, a beautiful replacement for an API or Neve console that few people know about. Their equalizer's were ferrite core inductors like Neve's. The microphone input transformers were the miniature Beyer's, but most of the great European microphones were designed into/around those transformers. Their integrated circuit chip the 409 as I recall, was one of the few to operate on +&-24 volts in comparison to most others 15 volt rails. This in combination with certain output buffering transistors made for one heck of a great sounding console with incredible headroom and low noise floor. It had a sweet fat sound that I still love to this day. I still have 10 inputs from that console and the master section that included 16 track monitoring. The microphone preamps were the 360 series. I have full documentation for that console, should you need it. The microphone preamps came in numerous different varieties. The 360BM, was the lowest noise version designed for integration within a console and was not designed to drive a 600 ohm load but had no problems loading into 10,000 ohms. From there, they had some higher current versions with a corresponding higher noise floor but able to drive lower impedance loads all the way up to 300 W DC operational amplifiers like a Crown Amplifier.

    I believe the company is still in business at 1033 Sycamore Drive, Santa Monica California? They also make video distribution amplifiers and other systems. At the same location as the "Hollywood Dolly" company, in the same building as Record Plant and the former Delos Records. I think the son runs the company now since Bel Losmandy, owner/founder has most certainly retired? At least I haven't spoken to him since 1978. He is one of the fathers of integrated circuit chip technologies and made an integrated circuit chip that sounded way better than any 709/741, etc.. I keep 8 of those 360BM preamps regularly in-service and use them frequently. Great for tracking directly into a digital multitrack.

    Enjoy your beautiful console as it sounds great! If you have any problems, don't hesitate to drop me a note.

    Op-Amp Labs Lover and aficionado since 1978
    Ms. Remy Ann David
     
  3. claymation

    claymation Guest

    Wow. Thanks a lot. It's been hard to find info on it. But that helps very much. It does have the 360 BM's by the way, and the EQ 250's. Neato.

    clay
     
  4. forasong

    forasong Active Member

    I have a full op amp 24ch studio board wired into a Skully 24 track 2in tape unit. (have 2 Skully 24 track machines) cant wait to get these all into the new studio and try it out.
     
  5. Front End Audio

    Front End Audio Active Member

    Wow! what a find. I guess I know what I will be doing every weekend all summer long! That is some really good garage sale luck!

    Cheers,
    Nicholas
     
  6. RemyRAD

    RemyRAD Well-Known Member

    24 track Scully?

    Those must be customized Scully 2" 24 track machines? Scully never made anything more than a 16 whether it was the 288-16 or the model 100-16. And what do you do for a 24 track Sync Master? Those machines can't fully erase any of the most recent hot tapes from Agfa/Ampex/3M or any of the new permutations. But it can certainly erase Ampex 456 Scotch 226 but not the Ampex 499 Scotch 250 Agfa 468. You just can't get a full depth of erasure. Beautiful sounding machines if you stick with the older tape formulations.

    Scully freak
    Mx. Remy Ann David
     
  7. moonbaby

    moonbaby Mmmmmm Well-Known Member

    Hmmm...
    He has "2 SKULLY 24-track machines"??? Well, maybe so. After all, I drive a Rollz Royce and a Meeata...
     
  8. forasong

    forasong Active Member

    yes 2 24-track skully 2in tape machines...one is for spare parts but as it sits it all works, one was the main deck.

    These were custom made I was told, i will post some pics sometime of them.

    Oh and Moonbaby, dont know what that comment is for but if ya want to be an ass I guess thats your option.
     
  9. moonbaby

    moonbaby Mmmmmm Well-Known Member

    Yeah, well I've been called worse before, and probably again in the future. Remy was a lot more tactful than I was, and that in and of itself is a blessed event:) But let's face it; your very first post here and you claim that you have not 1, but 2, machines that the manufacturer says they never made. BTW, I believe that Remy worked for SCULLY...and you did not answer her technical questions, all you did was get snotty about my ribbing you for not spelling the manufacturer's name correctly.
    FWIW, in 1977, when I was planning to expand my 8-track room to 24 tracks, I looked at (3) machine manufacturers:
    Ampex (already owned a couple of AG-440's to mixdown to)
    MCI (another studio here had a 16-track )
    Scully (because of Tom Scholtz and Boston)
    We nixed the Scully because the factory told us that they didn't make a 24-track machine, and that they were not interested in building one. Whoever we talked to back then ran off a litany as to what
    technical issues would be involved to pull this off. No way was I going to compete without a 24-track, period.
    The Ampex was a lot more $$ and the sales guy was a schmuck in a suit. So we went with Jeep Harned's JH rig and never looked back.
    Enjoy that rig, guy!
     
  10. RemyRAD

    RemyRAD Well-Known Member

    And here is a funny story when we were looking for a multitrack machine for our new studio. We realized that we were not going to go 24 track but rather 16 track 2". I went up to NYC to look at a couple of MM 1000-16 machines. One at Regent Sound Studios. I was shown the machine during a tracking session while it was in record mode. I couldn't see the singer in the band but it sure as heck sounded like Robert Palmer? When walking down the hall with Bob Loftin (the owner) I told him that guy sounded like Robert Palmer? He told me, " it was Robert Palmer". We opted not to get that monster. Instead, we purchased a brand-new MM 1200-16 that was on display, on the floor, at the AES at the Waldorf Astoria in 1978. We ordered 8 of their PURC cards (Pick Up Recording Capability). This was a significant option. In times gone by, when you punched in to record and then dropped out, there was both an overlap & a gap because of the difference in distance between erase & record heads. This made some punching impossible. But if you had the pickup recording capability without overlaps & gaps, you could punch like nobody's business. Unfortunately, the Ampex cards would not function without significant pops & clicks being introduced to the recording! Ampex didn't believe me when I told them their lousy cards didn't work. So they sent out a couple of senior factory technicians. These guys worked on the machine for 2 days only to take out their PURC cards and reinsert the originals. They said that their card had worked in the AG 440.??? So, I guess we were the first to try and purchase multiple cards for a MM 1200 which wouldn't work. No fix either. So we never had that feature on our MM 1200. I couldn't have produced the jingles I did down in Florida without that MCI JH-110A-8 because their pickup recording capability punch in WORKED! And it allowed me to to do things that couldn't be done until we got our computers 15 years later.

    And yes, I worked for Scully as their QC manager/final test technician and the primary troubleshooter on the 280B problems after the company was purchased from Dictaphone. I was there for less than a year before I decided to move on and they went belly up being purchased by Sequoia Electronics in Colorado. I still have a few sitting around.

    Old analog like old engineers belong together
    Mx. Remy Ann David
     
  11. forasong

    forasong Active Member

    Well you dont need to believe me, thats your choice and just because it was my first post here makes me a liar? wow with that kind of attitude it is a wonder anyone posts here.
    I never questioned anyones background on here either, I got these machines, I did nt say I was an expert with them. Hell, I dont actually know much about them at all I was actually hoping to learn more not get called a liar.

    Anyway, think I will move to a more helpful board.
    God speed
     
  12. moonbaby

    moonbaby Mmmmmm Well-Known Member

    I never called you a liar....you are certainly no speller :)
    So you've got not 1 but 2 Scully 24-track machines, 1 in use and 1 for parts, great !
    And you don't know much about them, so this is definitely the place to learn. After all,
    Remy is chock full of great tech information on them, probably the most knowledgeable
    in the country (if not the world) for Scully machines. Don't let ME keep you from obtaining that information, we all want to see analog kept in operation.
     
  13. RemyRAD

    RemyRAD Well-Known Member

    I'm certainly not trying to scare you off. I was only indicating that Scully never manufactured anything more than a 16 track machine. You indicated these were customized which is entirely possible. I've never seen one much less two. They are great machines. The Op-Amp Labs console is a terrific piece of early 1970s technology. Bel Los Mandy was one of the early fathers of integrated circuit technologies. While there were some usable IC chips back then few sounded as good as his 4009 op amp. He coupled that with additional output buffer transistors, input transformers, etc. into these fine little 8 Gold plated pin tube sockets. They had nice ferrite core inductor equalizers of which they had 2 different models. Their earlier model only offered shelving equalization at a few selectable frequencies. Their later equalizers offered bell shaped midrange frequency selections with high and low frequency shelving. Although some folks don't like those little Beyer microphone Transformers which is what he used in the 360BM/M preamps. The BM were slightly lower in noise but also have less output drive capability than the M preamp. So if you wanted to feed an Ampex or Scully and you didn't have the entire console you would want 360M preamps, since they could drive 600 ohm loads quite nicely. Just not as much of an issue with today's stuff that have 10,000 ohm or greater inputs. Just like API, Neve, Auditronics, these consoles while limited in their features could be considered of a boutique vintage quality piece. They used a bipolar 24 V supply unlike most of the other consoles. Most of the others utilized a bipolar 15 V or single polarity 24 V. So this console could swing 48 V on its rails which probably few people know. Although there were complaints about overload by folks that were utilizing factory built consoles. You could build your own from a box of parts if you wanted to. That's what I did but I utilized some different gain staging which I feel really improved the headroom we achieved with our console. Sure, my board was probably running a few DB more noise than the factory unit. But since we were aiming at the rock 'n roll market, that's really not a factor if you know what you're doing. The analog tape machine generated more noise than the console so it's really moot. I didn't use his output transformers but instead UTC A- 20's if memory serves me correctly. My output & monitor section was completely custom. I built the console so that it could also be expanded to 30 inputs but that but that never happened. Back in 1978 I spoke to Bel quite a number of times. For that matter, back in the day, I never thought twice about contacting a person or manufacturer of a piece of equipment to discuss their philosophy & maintenance concerns on their product. In fact, that's one of the ways I ended up becoming Scully's QC manager/Final Test Tech. When someone figures out you know their equipment better than they know their own, it's an employment prospect. And with the gear you have, you're going to have to get into the thick of it to keep it going and good sounding whether it's for yourself or for prospective clients. You might be working this stuff but I can assure you it will work you. Of course, I might be talking to myself and you're probably not here?

    I love to talk shop to myself. Really? Yup. I'll never forget when the take-up reel motor smoked on my used Curtis Mayfield JH 10-16. The next day it functioned like nothing happened...
    Mx. Remy Ann David
     
  14. martin12

    martin12 Guest

    Hello,
    There have been many excellent collections of op-amp circuits in the past, but all of them focus
    exclusively on split-supply circuits. Many times, the designer who has to operate a circuit from a
    single supply does not know how to do the conversion.
    Single-supply operation requires a little more care than split-supply circuits. The designer should
    read and understand this introductory material.

    thanks!!
    ______________
    buy cables online
     
  15. forasong

    forasong Active Member

    Ok I am back, Sorry I just picked all this gear up...my mistake, it was 2 16ch Skullys and a OpAmp studio board along with many other things like bunch of Gainbrain comps and Kepex limiters and a AKG BX5 spring reverb unit. I do not know much about this stuff but am hoping to get some help with it and get it up and running in the studio. I have all manuals, schematics and such for all the gear.
    Here are some pics, they are crappy and the gear needs some cleaning but here ya go. I also have 2 boxes of extra new mic pres and plug in parts for the OpAmp board.
    I would love any help I could get, thanks all.



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  16. Davedog

    Davedog Distinguished Member

    Welcome back. Maybe. Since it was mentioned to you on your first pass, I'll start here with it on your second. Please, go out to the garage or wherever you are storing this gear and look at the nameplate on the recorders. Notice it says "SCULLY" without a "K"....not "Skully". Just wanted to get that out of the way.

    Now hopefully, Remy will get with you on this collection of stuff and help you out. It wont get any better than that source of information so dont get defensive and all out of shape when someone simply wants to correct you and get you going down the right path.

    Love the Kepex's BTW as well as the AKG reverb. But then I'm old school too......Still have the OLD Allison badges!!!!

    peace.....(remember, you own SCULLY tape recorders)
     
  17. moonbaby

    moonbaby Mmmmmm Well-Known Member

    Amen to that ! !
    I remember the first studio I worked in had GainBrains and Kepex's. Those Kepex's chattered worse than an Eskimo's teeth on the North Pole ! ! Looks like Remy was right- the recorders are 16 tracks...
     
  18. forasong

    forasong Active Member

    yes Remy was right.
    I was told before I saw them that they were 24ch machines, though I am very happy with them being 16ch, either way works for me. Sorry I keep spelling Scully wrong, wont happen again.
    There was a bunch of other gear as well including many new rolls of Tape and some very cool old keyboards. I am hoping we can get on the right track this time, thanks for the info on the gear all.
     
  19. RemyRAD

    RemyRAD Well-Known Member

    OMG! Yup, you hit the mother lode!

    It's obvious that you have an early release Scully 288-16 actually made in Bridgeport before the Dictaphone purchase of Scully. That particular machine is the finest sounding of the Scully 280 series. Most of the silver faced electronics indicates Bridgeport Connecticut manufacturing. If they were beige, it would indicate a Dictaphone built machine. And to make sure that this is not been modified to the later, newer silicon transistors, pull out any of these circuit cards from the electronics. Look for the transistors. If you find little black & silver metal cans with GE imprinted, you have the original germanium transistors. If the transistors are black, smaller all epoxy/plastic transistors, it has been modified. This modification also required changing other prerequisite resister's since the voltage drop for geranium transistors is different than that of silicon. Many boutique microphone preempts today utilize germanium transistors. So what you have there is 16 channels in the Scully of unique boutique microphone preempts.

    Now onto that Op Amp Labs console. Wow! Looks almost identical to the one that I built in 1978. These were early integrated circuit chips that actually sounded quite tasty. The equalizers while being somewhat limited utilize lovely ferrite core inductors and are quite NEVE like. I still have the master section & 10 inputs from my 20 input console I built. So between your Scully microphone preamp's and the Op Amp Labs desk, you've got an incredible sounding facility.

    Yup, I still have 8 of those Allison Research KEPEX's in the control room. They only chatter if you do not understand how to utilize them properly. Threshold, release time & proper setting of just enough downward expansion generally solves the chatter problem. I never cared much for their Gain Brain comp/limiter but that was probably due to my own operator error? But between those & the KEPEX's (or should that be KEPEX' ? English grammar was never my best subject) you have some fabulous drum processing in the making. I usually used UREI 1176's followed by the KEPEX as my favorite way to process much of a drum kit. Plus your KEPEX' when utilized for only 10 to 15 of downward expansions makes for some quite effective tape track noise reduction and didn't have quite the same dulling effect that Dolby A imparted upon the sound of the tape. Of course the KEPEX was essentially an early, all transistor VCA. So there is a slight mush like quality that you will find from the KEPEX. One of the biggest problems you'll find with the KEPEX is probably the need to replace every electrolytic capacitor on every one of those KEPEX & Gain Brain cards. Otherwise, if you don't, they won't work worth a damn. Looking at the colored knobs indicates these were the later release of the Brains & KEPEX'. The earlier version (original release) utilized aluminum knobs and all of the visual indicators were neon bulbs. This required the power supply to have an additional 100 V circuit to make the neon bulbs work. A later upgrade could be made to LEDs which I had to do to 4 of my 8 but you already have the LEDs.

    My friend you have one heck of a classic sounding boutique control room where the balls, rather than the sky are the limit! You'll make great recordings with what you've just gotten. The console sounds as beautiful as any API or NEVE of the same late 1960s era. Totally Awesome!

    Now here's the really exciting part. Since most of us have to incorporate some kind of digital technologies within our recording systems, all you really need now is a used Alesis HD 24xr (or stock HD 24). You'll only need 2 roles of 2 inch tape. When you start tracking your sessions, you should provide headphone fold back through the Op Amp console. But at the same time, you'll be rolling to the 288-16 in record/repro mode. The output of which will be sent directly to the HD 24. That's the ticket! Overdubbing will require a little more tricky time displacement realignment which will require a little imaginative thinking OTB.

    One of the other things you should know about the 288-16 is that the "linearizer" adjustment should be completely disabled utilizing any modern day recording tape. The linearizer was designed to create an inverted distortion element that would gain you 2 DB of additional headroom or lower noise level. It is not applicable to any modern-day recording tape. To disable the linearizer the adjustment control must be turned fully clockwise and not counterclockwise. It's a common mistake made by many. You can verify that the linearizer is not in operation when feeding the machine and a 1 kHz sine wave at 0 DB. When you press the momentary recessed red pushbutton, the playback level should not change. It shouldn't go up, it shouldn't go down. If it does, the linearizer adjustment control may have been reverse wired since lots of people had issues of turning it off by turning it up.

    There can be additional problems with certain situations involving the last series of super hot recording tape such as Scotch 250 and it's Ampex & Agfa cousins. Without extensive wiring modifications the hotter tapes do not fully erase which will leave audible garbage behind. So for convenience of operation, one shouldn't use anything other than Scotch 206/226, Ampex 406/456 (I can't remember the Agfa tape model number that'll work?) These will yield the best results with the 288-16's, 284/280's series. I believe that the "Wolke" full width " Staggered Gap" erase heads will allow full erasure with the latest hot state-of-the-art recording tapes. Other folks have indicated that a replacement of the erase head wiring with a much heavier gauge conductor can improve erasure with the original NORTRONICS erase head but I have not personally verified that. So if you're not going to worry about erasing anything or doing overdubs on the 288-16, you can use the hotter tapes even though your bias adjustment will be " balls to the wall" to make that happen.

    The noise adjustment on the 288-16 provides a small DC offset in the recording circuitry to the head. This can help eliminate some of what we called " bias rocks". This is best done when feeding the machine in a very low frequency i.e. 30 Hz sine wave. Monitoring on playback while recording, you can adjust the noise adjustment to reduce the rocks or gravel like sound. But this is also dependent upon bias level as well. Normally, most folks would over bias by 2 DB at 10 kHz which was pretty darn close when utilizing Scotch/Ampex 206/406 tape. Conversely, the John Stephens method of utilizing a 10 Hz sine wave function generator while clobbering the tape fairly aggressively & listening to playback and adjusting bias for lowest modulation noises & rocks makes for much smoother bass response and is generally equivalent to +2 DB over at 10 kHz. Of course, it's only my personal preference that I like rocks with my Scotch, if I am a Dewar or the Glenlivet. Of course R&B goes well with J&B. Of course if you want to enjoy the finest sound with your beverage, you might want a Remy'?

    What have I forgotten? Oh yes! The shot glass effect!
    Mx. Remy Ann David
     
  20. Davedog

    Davedog Distinguished Member

    I hope some of you younger enthusiasts of vintage sound read this. If you insist on using a tape machine, THIS is the way to do it. The only pass the heads will see is the intial recording pass with the output to the converters and direct to a harddisk or PT or whatever DAW you like. The bias and alignment will only have to be for the type of tape you can find easily and the desire for that big clear compressed sound will be there for the money.

    Talk about a hybrid system!!! This methodology will work with ANY size/speed/track number tape equipment.

    Glennfiddich, neat and old enough to vote.
     

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